There’s an interesting economic crisis point coming alongside plummeting solar and battery costs. At some point soon, the cost of installing battery backed solar on private properties will be cheaper than the cost of the wiring for the grid. At that point, even if the electricity feeding the grid cost zero dollars to produce, the grid itself will cost more than generating your own power. So, from a purely financial perspective, anyone who has the space to install solar should install solar.

This leads to an interesting feedback loop. We can’t shut down the grid, because there are people in apartments and things that need it – not enough surface area on an apartment roof to generate enough solar. So they will still have to pay for the grid. With fewer and fewer grid connected buildings, however, the cost of maintaining the grid disproportionately goes to those without land. This dramatically alters the value of land in favour of those that own it. It feeds sprawl, and exacerbates the gap between the rich and the poor.

Industrial users will bear much of the grid cost – most factories cannot power themselves with solar, particularly those in high energy industries. But, it’s possible that the high energy factories just buy farmland so they can set up mostly autonomous facilities outside the cities. Not solar, but this is a good example: ammonia plant building its own wind farm in the middle of nowhere https://www.cbc.ca/news/canada/newfoundland-labrador/evrec-marine-group-wind-hydrogen-ammonia-botwood-grand-falls-central-1.6754995

Long short: expect there to be social disruption due to low solar and battery prices. Deurbanization is a likely byproduct.